For a customized fit and ventilation for all day comfort on hikes and rides the Osprey Sirrus 24 is the pack to go with. This pack features three torso sizes so you can adjust this pack to fit you comfortably. The stretch mesh back panel allows warm and moist air to escape. A main compartment with panel loading allows you to access your gear in the Sirrus 24 quick and easy. Two side pockets and a zippered hipbelt pocket give you additional storage space for all of your gear. An integrated rain cover allows you to keep the Osprey Sirrus 24 protected from the elements should Mother Nature decide to drop some rain on you.